Tact-tiles would probably be up your alley. A chessex battlemat would probably do you good as well. Piazo puts out some preprinted mats that have many uses.
If you have the money, there's some folks that have set up projectors (mounted on the ceiling, pointing down) to display maps on the game table - when coupled with a PC. I've also tried using a LCD display (laid on its back) to project a map, but you have to be careful about spilled drinks. Also, there's a group that is designing a "map table" for the microsoft surface - but you're talking big bucks there.
Personally, though I like Dungeon Tiles for how fast they can be laid out (if you have them organized, in say a tackle box), I prefer Dwarven Forge or Worldwork Games printable cardstock tiles for their great looks. The latter has some ingenious methods for storing and setting up the pieces really quickly (tacking them to a wall or corkboard for storage, and a velcro mat for quick setup).
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Edit: if you want a do-it-yourself project, you could buy one of those cheap poster frames at Walmart or such as a base. Take the clear plastic "glass" and draw a grid up on it with permanent marker. You can then print out maps and place it under the "glass" for an instant battlemat. If you print stuff out ahead, you could "reveal" a room at a time fairly quickly. It would probably work best if you could elevate the "glass" slightly so you could quickly slip the map in underneath without having to disturb the miniatures on top.
Also, you could do quick setups with dungeon tiles - get a thin piece of cardboard and some rubber cement. Before the game, use a few drops of the rubber cement to temporarily affix the tiles to the cardboard. When players enter a new area, you simply lay down the new area. When you no longer need it, you should be able to easily remove the tiles from the cardboard without damaging them.
Also, on the "regular shape for irregular rooms" - there is a cavern set for the tiles OR, assuming you can get an extra set or two, a pair of scissors/x-acto knife applied to the tiles can be used to make you some custom pieces or edges that could be used for making caverns or unusual shaped rooms (such as round rooms, or rooms with slanted walls).
You could also set down the dungeon beforehand by whatever method you want and using paper or a cloth covering over the whole thing, reveal the dungeon in sections without giving away the whole structure at once. Just be careful to not make each covering the exact same size/shape as the part you're revealing.
